For ease of reference, this is a compilation of general tech/maintenance recommendations from various members of the Turbo Dork Scooter Network.

SPARK PLUGS/TIMING:

From Mikeh:

I've never trusted or been a fan of "plug chops" or checking the color of the spark plug.

The best way to tell if your motor is tuned right is to just ride it, listen to it, and smell the exhaust.

You can also check the timing with a timing gun to see if you are in the correct ball park with specs.

If the exhaust is smokey and it rides slow and cool you are probably running too rich. If the exhaust is clean and the motor winds out very fast and the cylinder shroud gets too hot to touch, then you're too lean.

If it backfires.. then you have ignition happening too late, it probably will run cool and sluggish. If it fires too early it may run hot and seize, but it will wind out faster.

The way on timing is to set it to factory recommended settings and vary it slightly from there. making sure to get good performance but not run it so hot that it explodes or backfires. it's a balancing act.

But I would not trust plug chops. When you kill the ignition and/or fuel to do the chop you will not get an accurate view of what is going on in there as the fuel mixture will still be getting sucked through the carb even if you turn the gas off (there is enough gas to let the engine run for about 30 seconds) So getting the fuel and spark to stop at the same time to get a good reading it not very likely.

From dirtyhandslopez:

All of the above Mike and also, the way to do plug chops, as told to people, is to WOT in third, then cut the ignition and turn off gas. Yeah, that's really good for a two stroke, get it hot then cut off the fuel that cools everything down. Kinda like coming off of the freeway, running full blast, then, shutting the throttle off, what you get is an insta seize. Run 'em and listen to 'em,smell em beat the hell out of them, but don't be shutting of the gas at high revs.

Mike, one problem with the whole torqe setting part is that very few people actually own a torque wrench, that alone one that is calibrated.

As a general guide, 15ftlbs is a regular 3/8 rachet(in length) used until it is tight, but not straining on the wrachet. Two white knucles, not four It's really best not to use anything over a 1/4 drive wrachet on any fastener under and including 5mm as you will tempted to torque down to hard. This is especially true if you have steel going into aluminum.Always try to use a flat and a lock(spring) washer. Lock/spring washers operate correctly only in one direction. If they are fitted backwards, they will "unwind" when you do them up. Have a look at one, you will see that one end has a flair, that flair should pressed down into whatever it is you are trying to secure, not pulled up into the nut or bolt head.